The autonomous navigation performance during the mars atmospheric entry is one of the key factors to affect the capability of mars landing. During this phase, since few types of navigation sensors are available and large uncertainties exist in environment and aerodynamic parameters, the design of the autonomous navigation method is complicated. In this paper, the principles of current mars entry navigation methods are summarized and their advantages and disadvantages are compared. With respect to these disadvantages, the methods that can improve the navigation performance are also discussed.

Input shaping and closedloop feedback control are combined to realize the vibration reduction of spacecraft with flexible appendages during the attitude maneuver control. To ensure the validity of input shaping for suppressing the vibration of flexible appendages, the effect of uncertain parameters, such as system inertia and modal matrix, are considered during the attitude maneuver. A method to calculate the model parameters of input shaper, which is based on maximum residual vibration, is proposed. And the impact of uncertain parameters to vibration reduction of flexible appendages is quantitatively analyzed, which can be as a theoretical basis for selecting proper input shaper. It reduces the conservation of traditional input shaper and contributes to enhance the control performance. Simulation analysis indicates that  the vibration suppression with considering system uncertain parameters is better than without them.

The attitude control of satellite with flexible appendage and rotatable payload is investigated. Attitude dynamics equations and rotatable payload torque model are presented on the basis of NewtonEuler method with generalized coordinates. The theory and characteristics on imbalance torque of rotatable payload are analyzed. Secondly, the influence of payload disturbance characteristics on attitude of satellite is studied, and the estimation method of attitude jitter is illustrated based on Laplace transform of transfer equation. Finally, the condition of a disturbance reduction controller is developed, which is applied to the satellite attitude control system, and the controller engineering application method is presented. The verification results show the effectiveness of the proposed approach, and the accuracy of satellite attitude is improved.

A new attitude control method for single gimbal control moment gyros (SGCMGs) that is based on angular momentum domain is presented. In this method, the attitude error is translated to SGCMGs’ angular momentum requirement (rather than torque requirement) without having to consider singularities. With double parallel SGCMGs, the SGCMGs are free to perform their eigenaxis time optimal path, when the RWs compensate for the variable unexpected system angular momentum bias. Meanwhile, similar strategy is designed for single gyro failure. Numerical simulations demonstrate that control law in angular momentum domain does not involving singularity, meanwhile with the capability of rapid maneuver and high-level stabilization.

This paper reviews the development of Satlet. A new concept is proposed by developed countries such as Japan, America and Germany. And the approach to realize Satlet is concluded. It is recommended to initiate the research on general Satlet technology, insitu reconfiguration technology and bionic Satlet.

The point cloud data registration is one of the key technologies of threedimensional reconstruction. To solve the registration issue of sparse point cloud scanned from the noncooperative spacecraft, we propose a improved 4points congruent sets (4PCS) algorithm to obtain the preliminary registration result, and optimize the final alignment with the improved iterated closest points (ICP) algorithm. Then，a novel point cloud simplification algorithm using uniform sampling is proposed based on KDTree. The uniform relation of the threshold parameters is established via the density of the point cloud. The results show that the proposed algorithm can effectively achieve good alignments of the sparse point cloud of the satellite, and the consuming time is decreased to 42.49% compared with the Geometric Hashing algorithm.

The spacecraft on the tourist orbit can travel around the GEO without control force. There are some disadvantages with the groundbased exploration network, so that the tourist orbit is supposed to improve the surveillance capability .In this paper, a initial orbit design is improved based on the previous design. Then by applying the control, two methods are proposed to observe the multiple targets on the GEO. Finally, simulation validations are given and their respective advantages are compared.